Sliding clasp fastener stringers

ABSTRACT

A slide fastener stringer comprising a knitted tape and a series of coupling elements secured thereto during knitting by an auxiliary sewing thread.

United States Patent Austin et al. 1451 Apr. 25, 1972 1.54 SLIDING CLASP FASTENER [56] References Cited SIRINGERSD UNITED STATES PATENTS [72] inventors: Christopher Frederic Austin; Philip Simp- 3 176 637 4/1965 Mach: 112/105 son Crowther; Dlvld Warren, all of Sutton Coldfield; David Howitt, Birmingham, all of England 1 Lightning Fasteners Limited, Birmingham, England Filed: July 6, 1970 Appl. No.: 52,190

Assignee:

us. c1 ..66/86, 112/265, 1 12/105 1111. c1. .1104 22/00 F1410 oiSearch 12/105, 265; 24/2051 c, 205.13 c,

Primary Examiner-Ronald Feldbaum Attorney-Cushman, Darby & Cushman [57] ABSTRACT A slide fastener stringer comprising a knitted tape and a series of coupling elements secured thereto during knitting by an auxiliary sewing thread.

9 Claims, 9 Drawing Figures PAIENTEU APR 2 5 I972 SHEET 2 BF 7 PATENTED APR 2 5 1972 ShEET H []F 7 1 SLIDING CLASP FASTENER STRINGERS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to sliding clasp fastener stringers and to methods and machines for their manufacture.

2. Description of the Prior Art A sliding clasp fastener comprises two stringers, each stringer comprising a series of coupling elements secured to a carrier tape. It is now well known to provide a series of interconnected coupling elements formed from a length of plastics filament which is either wound in a coil shape, or is formed into a meander configuration which is folded along its centerline into U-shape. A fastener having a coil-shape element construction will be referred to hereinafter as coil fastener construction" and one having U-shaped elements will be referred to hereinafter as meander fastener construction. Other forms of interconnected coupling elements have been proposed wherein the elements are produced by notching a tube of plastics material or by molding a series of elements having interconnecting portions formed integrally with the elements.

SUMMARY OF THE INVENTION According to the present invention, a method of making a sliding clasp fastener stringer comprises warp-knitting a carrier tape and, during the knitting, locating a series of interconnected coupling elements at one face of the tape and adjacent a longitudinal edge of the tape as it is knitted, passing a binding thread by reciprocating movement of a sewing needle between adjacent coupling elements of the series to form a stitch loop at the other face of the knitted tape beyond the hooked end of a knitting needle employed in knitting the tape, and moving the hook of the knitting needle through the stitch loop so that the hook engages the loop and interlinks the loop with a yarn of the knitted tape.

The sewing needle may move in thelapping sense of the yarn guides of the machine when the sewing needle is at the front of the machine and between its reciprocating movements to effect a zig-zag pattern of binding thread on the face of the coupling elements remote from the tape and two series of laterally spaced stitch loops on the other face of the tape, one series being engaged by a first knitting needle and the second series being engaged by a second knitting needle. Twin sewing needles may be employed to feed two binding threads to form two series of stitch loops extending longitudinally of the elements the loops of each series being engaged by a respective one of two knitting needles. Preferably each of the twin needles is also caused to move in the lapping sense of the yarn guides of the machine when the sewing needle is at the front of the machine and between its reciprocating movements.

The series of coupling elements may be of known coil or meander fastener construction and may comprise a cord or braid disposed between arms of the coupling elements to minimise slipping of the binding thread across the elements. In the case of the single sewing needle not having a swinging movement, the needle may penetrate the cord or braid. In the cases of the single needle having a swinging motion, or of the twin needles, the needle or needles may penetrate the cord or braid, or may pass either side of the cord or braid.

Instead of or in addition to the cord or braid, the coupling elements may have notches or depressions in their outer surfaces to prevent slipping of the binding thread across the elements.

The series of coupling elements is conveniently guided through a tubular guide to its position adjacent an edge of the tape being knitted.

The invention also includes a warp-knitting machine for making a sliding clasp fastener stringer, the machine having a knitting zone and comprising a row of knitting needles for knitting a carrier tape of the stringer, a plurality of guide bars each carrying yarn guides, a tubular guide having a lower end disposed to guide a series of interconnected coupling elements to a predetermined position in the knitting zone adjacent one end of the row of knitting needles, a sewing needle disposed at the front of the machine and means for reciprocating the sewing needle through a plane containing the row of knitting needles in a position beneath the tubular guide whereby during use the sewing needle passes a binding thread from the front to the rear of the machine, said thread passing around coupling elements being guided from the lower end of the tube, the needle coacting with at least one of the knitting needles to knit the binding thread into the tape and secure the elements thereto.

The tubular guide is preferably supported in a fixed position relative to the plane of movement of the knitting machine.

Means may also be provided for moving the sewing needle in directions in the lapping sense of the yarn guides when the needle is at the front of the machine so that the needle acts to form stitch loops of binding thread on at least two different knitting needles of the machine.

Two sewing needles may be provided to feed two binding threads to two knitting needles.

The invention also includes a fastener stringer when made by a method or with a machine so defined above.

BRIEF DESCRIPTION OF THE DRAWINGS Three embodiments of the invention and modifications thereof will now be described by way of example only and with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a first fastener stringer construction being made on a warp-knitting machine and illustrating the first embodiment;

FIG. la is an isometric view of part. of a practical machine according to the first embodiment;

FIG. 1b is an isometric view of other parts of the machine, and

FIG. 1c is an end view of part of the machine;

FIG. 2 is a perspective view of a second fastener stringer construction being made on a knitting; machine, illustrating a second embodiment, and

FIG. 2a is an isometricview of part of a practical machine according to the second embodiment;

FIG. 2b is a view similar to FIG. 2a of further machine, and

FIGS. 3 and 4 are perspective views of a stringer construction being made on a warp-knitting machine and illustrating a third embodiment.

parts of the DESCRIPTION OF THE PREFERRED EMBODIMENTS The first embodiment will now be described initially with regard to FIG. 1 which shows diagrammatically, parts of a three guidebar warp-knitting machine are represented as follows: numeral 10 designates a trickplate in which is slidably mounted a row of latch needles 11. Yarn guides 13 movable in known controlled manner with respect to the latch needles by a plurality of guide bars as will be described. Each guide bar carries yarn guides 13 through which yarns 14 are fed to be knitted into a carrier tape 15 at a knitting zone of the machine.

In a first embodiment (FIG. 1) which relates to a machine for making coil fastener construction, a series of coupling elements 16 in the form of a coil of plastics filament having a series of longitudinally aligned coupling heads 17, and surround ing an inner textile cord 18 is fed downwardly with the cord through a tubular guide 19 as for example, by a ratchet operated toothed wheel as will be described. The tubular guide 19 is fixedly mounted in a bar 19a secured between end frames of the machine. The lower end of the guide 19 is located at a predetermined position adjacent a longitudinal edge of the tape 15 at the knitting zone and the guide is inclined forwardly of the machine to permit the lapping movements of three series of yarn guides 13 between the needles l1 and the guide.

A sewing needle 20 is disposed at the front of the machine and perpendicularly to the general plane of the tape 15.

Operating means as will be described, working in synchronism with the operation of needles 11 and guides 13, are provided to pass the needle in a reciprocating manner below the tubular guide 19 and through the plane of the needles 11. The sewing needle 20 passes through the cord 18 to feed a binding thread 21 through the cord and between adjacent coupling elements 16.

In operation, when the latch needles 11 are in the lowermost position, the sewing needle 20 is advanced through the cord 18. As the needle 20 is withdrawn, the frictional grip effected on the thread 21 by the cord 18 enables a stitch loop 22 to be formed above a latch needle 11a at the rear of the tape. The timing of the latch needles 11a and sewing needle 20 are so arranged that as the latch needles rise, needle 11a is inserted through the loop 22. One of the yarns 14 is then lapped across the needle 11a and subsequent lowering of this needle links the loop 22 into the knitted tape 15.

As the series of coupling elements are fed with the progressively formed tape, the needle 20 is synchronously moved between successive pairs of coupling elements 16 so that a series of loops 24 of thread 21 is formed over the series of coupling elements on the side remote from the knitted tape 15.

Considering now a practical form of the machine in more detail, reference is made to FIGS. la through 10. In the machine a plurality of sewing needles 20 are located in needle holders 50 which are spaced-apart along a needle bar 51 extending along the front of the machine, the holders 50 being located by screws 52 in holes 53 in the needle bar. Only one holder 50 is shown in FIG. 1a for clarity. The needle bar 51 is mounted along its length at intervals upon levers 54 which are pivotally mounted upon a shaft 55 secured to the machine frame. A motion of the needles along substantially rectilinear but slight arcuate paths between the tubular guides 19 and adjacent coupling elements 16, as described with regard to FIG. 1, is produced by pivoting of the levers 54 in a controlled manner. This controlled movement is provided by a cam follower 56 on an arm 57 of each lever 54, the cam follower being in engagement with a peripheral cam surface 58 of a cam 59 which itself is secured to a shaft 60 (FIG. 1c) which is drivable in synchronism with the rest of the machine. FIGS. la and also show material holding blades 61 which are disposed on an L-shaped bracket 62 extending along the machine at the back of the needles 11. The material holding blades 61 are moved as in normal manner for knitting machinery by a lever 63 to which the bracket 62 is secured, the lever being pivotally mounted upon the shaft 55 and pivotally movable by an actuating rod 64 which is moved in synchronism with the movement of the needles 11. The movement of the holding blades 61 is thus synchronized with that of the needles 11 so that the blades 61 occupy the position shown in FIGS. 1a and 10 during movement of the needles 11 between them whereby knitted tape material is held down and is not forced upwards by the needles themselves. The levers 63 are moved in an anti-clockwise direction as shown by arrow A in FIG. 1c and out of the path of the needles 11 when the needles 11 move downwardly after a knitting operation to enable the last course of knitted material to pass beneath the blades 41 in preparation for the next holding operation.

A plurality of needle guides 65 are of conventional construction and operate in the normal manner for knitting machinery.

The yarn guides 13 are mounted upon four guide bars 66 which extend horizontally across the machine and hold groups of guides 13 for guiding the yarns 14, one group for each tape. In FIG. 1a one group of guides is shown. The guide bars 66 are movable in horizontal manner as shown in FIG. lb by a drive rod 67 which is connected at one end to a block 68 mounted on the guide bar and is secured at the other end to a block 68 mounted on the guide bar and is secured at the other end to a short rod 69 movable axially in a housing bracket 70 mounted on part of the machine frame 71. Each guide bar 66 is urged in conventional manner in knitting machinery towards the right by spring loading so that a cam follower 72 on the end of short rod 69 engages the peripheral cam surface 73 of a cam 74 secured to a drive shaft 75 which is rotatably mounted and drivable in the machine frame. Movement of each guide bar 66 by the cam 74 provides the lapping movement of the yarn guides 13 attached to that guide bar in the normal way for knitting machinery so as to perfonn knitting operations in conjunction with the independent lapping movement of the other guide bars. At intervals each guide bar 66 is mounted by a bracket 76 to an arcuate arm 77 which is pivotally mounted for swinging movement in a vertical plane upon a horizontal shaft 78 which extends from side-to-side of the machine. Each bracket 76 is connected to the arm 77 by pins 77a upon which the bracket 76 is slidable. Movement of the arm 77 in its vertical plane provides simultaneous swinging movement of the guide bars 66 and thus of the yarn guides 13 in a conventional manner for knitting machinery to move the yarns 14 between positions at the front and rear of the knitting needles. This movement is provided by a crank 79 and a connecting rod 80 with one end of the crank being secured to the shaft 78.

The machine described with reference to FIGS. la, b and c attaches the coupling elements 16 to the tape during knitting in the same way as has been described for the basic construction with reference to FIG. 1. The knitting operation for each tape is performed in conventional manner by swinging movement of the yarn guides 13 by movement of the crank 79 so as to pivot the arms 77 upon the shaft 78, and also by lapping movement of the guides caused by horizontal movement of the guide bars 66 controlled by the cam 74 as described above. With the latch needles 1] at their lowennost position after knitting one course of each tape, the sewing needles 20 are reciprocated forwardly and rearwardly of the machine by operation of the lever 54 upon the shaft 55 by the cam 59. Each needle 20 moves through a cord 18 to form a stitch loop 22 above a respective latch needle 11 so that as the needle bar 101 with the latch needles 1 1 rise, the appropriate needles are inserted through the loops 22. With subsequent lapping of the yarns 14 and lowering of the latch needles, the loops 22 are knitted into the tape 15.

In a second embodiment (FIG. 2) relating to a machine for making meander fastener construction, a stringer being made on the machine comprises a series of coupling elements 25, the arms 26 of each coupling element being mounted astride a braid 27. The series of elements 25, together with the braid, are fed downwardly through a suitably shaped stationary inclined tubular guide 28 to the knitting zone. A sewing needle 30 has an operating means to pass the needle in its axial direction beneath the tubular guide and also as will be described to swing the needle in a horizontal lapping sense of the yarn guides of the machine when the needle is at the front of the machine so that the needle may pass alternately at either side of the braid 27. The needle 30 may penetrate the sides of the braid to provide a frictional holding means for a binding thread 31 fed by the needle to effect a stitch loop. A1- ternatively, if the needle 30 does not penetrate the braid 27, felt pads (not shown) may be provided at each side of the braid to frictionally engage the thread 31.

Another means of frictionally holding the thread 31 is to provide resilient fingers between which the needle 30 passes. By means of the horizontal swinging movement of the needle 30, the thread 31 is looped alternately around latch needles 29 and 29a to be interlinked with loops of the knitted tape 15.

For example, referring to FIG. 2, the thread 31 is looped into an edge of the knitted tape as at position 33 which is one of a plurality of spaced positions in a first series of loops at one side of the braid. The thread passes to the front of the structure and progresses angularly across an arm of a coupling element to be looped into the tape at position 34 which is one of a plurality of spaced positions in a second series of loops at the other side of the braid. The thread 31 returns to the front of the structure, progressing angularly across an arm of the next successive coupling element and is looped in at the edge of the tape at position 35. Thus, by virtue of the horizontal swinging movement of the sewing needle 30, the auxiliary thread 31 assumes a zig-zag arrangement of stitching 36 at the face of the series and forms two series of stitch loops. The needle 30 cooperates with two knitting needles 29, 29a as with the needle 11a in the first embodiment, so that the two series of loops are held by needles 29, 29a and knitted into the tape.

A practical machine for performing the second embodiment is described with reference to FIGS. 2a and 2b, most parts of which operate in a similar manner to those described in the first embodiment with reference to FIGS. 1a through 1c, and like parts bear like reference numerals. In the second embodiment, however, the needle bar 51 is slidably mounted between a lower slideway 81 and upper guides 82 so as to be movable horizontally across the front of the machine to effect move ment of the sewing needles 30 in the lapping sense of the yarn guides.

Sliding movement of the needle bar 51 is effected by means of a drive shaft 83 which is secured at one end to the needle bar and at its other end carries a short shaft 84 slidable within a housing 85. A cam follower 86 on the end of the shaft 84 lies in engagement with a peripheral cam surface 87 of a cam 88 secured to the drive shaft 75. The needle bar 51 is spring loaded towards the right as viewed in FIGS. 2a and 2b so that the cam follower 86 always engages the cam surface 87.

In a third embodiment (FIGS. 3 and 4), the stringer construction produced is the same as that produced by the machine of the second embodiment (FIG. 2) employing a horizontally swinging sewing needle. However, in this third embodiment a sewing needle 40 is moved solely in a reciprocating manner as in the first embodiment. The zig-zag arrangement of binding thread 41 is effected by oscillating a tubular guide 42, through which a series of coupling elements 43 and its braid44 is fed, in a plane substantially parallel to that of the knitting needles 45. Oscillation of the tubular guide 42 is obtained by the actuation of a connecting rod 46 pivotally connected at its one end to one face of the guide 42 by pin 47 and connected at its other end to a rotatably driven crankshaft (not shown) geared to the main drive of the knitting machine. The tubular guide oscillates about a position lying on the longitudinal axis of the braid 44 and below the sewing needle 40. The angle through which the tubular guide 42 oscillates is sufficient to locate the braid 44 alternately on each side of the path of movement of the sewing needle 40 at each reciprocation of the needle. The resultant pattern of the binding thread 41 is thus similar to that illustrated in FIG. 2 of the drawings.

In any of the above embodiments, the series of coupling elements may be varied so that in the first embodiment (FIG. 1) for instance, the series of coil-type coupling elements 16 may be replaced by a series of meander type coupling elements 25 as employed in the second embodiment (FIG. 2). Further, in any embodiment the series of coupling elements may be employed without an internal cord or braid.

Whereas the above embodiments have been described in relation to machines employing latch-type knitting needles, the invention may also be performed with machines using bearded-type or compound-type needles.

We claim:

l. A method of making a sliding clasp fastener stringer comprising warp-knitting a carrier tape and, during knitting, locating a series of interconnected coupling elements at one face of the tape and adjacent a longitudinal edge of the tape as it is knitted, passing a binding thread by reciprocating movement of a sewing needle between adjacent coupling elements of the series to form a stitch loop at the other face of the knitted tape beyond the hooked end of a knitting needle employed in knitting the tape, and moving the hook of the knitting needle through the stitch loop so that the hook engages the loop and interlinks the loop with a yarn of the knitted tape.

2. A method according to claim 1 wherein the sewing needle is caused to move in the lapping sense of the yarn guides of the machine when the sewing needle is at the front of the machine and between its reciprocatin movements to effect a zlg-zag pattern of binding thread on t e face of the coupling elements remote from the tape and] two series of laterally spaced stitch loops on the other face of the tape, one series being engaged by a first knitting needle and the second series being engaged by a second knitting needle.

.3. A method according to claim 1 wherein the series of coupling elements is of coil fastener construction.

4. A method according to claim 1 wherein the series of coupling elements is of meander fastener construction.

, 5. A method according to claim 1 wherein a cord or braid is disposed between arms of the coupling elements and extends longitudinally of the series of elements.

6. A method according to claim ll wherein the series of coupling elements is guided through a tubular guide to its position adjacent an edge of the tape being knitted.

7. A warp-knitting machine for making a sliding clasp fastener stringer, the machine having a knitting zone and comprising a row of knitting needles for knitting a carrier tape of the stringer, a plurality of guide bars each carrying yarn guides, a tubular guide having a lower end disposed to guide a series of interconnected coupling elements to a predetermined position in the knitting zone adjacent one end of the row of knitting needles, a sewing needle disposed at the front of the machine and means for reciprocating the sewing needle through a plane containing the row of knitting needles in a position beneath the tubular guide whereby during use the sewing needle passes a binding thread from the front to the rear of the machine, said thread passing around coupling elements being guided from the lower end of the tube, the needle coacting with at least one of the knitting needles to knit the binding thread into the tape and secure the elements thereto.

8. A machine according to claim 7 wherein the tubular guide is supported in a fixed position relative to the plane of movement of the knitting needles.

9. A machine according to claim 7 wherein means are provided for moving the sewing needle in directions in the lapping sense of the yarn guides when the needle is at the front of the machine so that the needle acts to form stitch loops of binding thread on at least two different knitting needles of the machine. 

1. A method of making a sliding clasp fastener stringer comprising warp-knitting a carrier tape and, during knitting, locating a series of interconnected coupling elements at one face of the tape and adjacent a longitudinal edge of the tape as it is knitted, passing a binding thread by reciprocating movement of a sewing needle between adjacent coupling elements of the series to form a stitch loop at the other face of the knitted tape beyond the hooked end of a knitting needle employed in knitting the tape, and moving the hook of the knitting needle through the stitch loop so that the hook engages the loop and interlinks the loop with a yarn of the knitted tape.
 2. A method according to claim 1 wherein the sewing needle is caused to move in the lapping sense of the yarn guides of the machine when the sewing needle is at the front of the machine and between its reciprocating movements to effect a zig-zag pattern of binding thread on the face of the coupling elements remote from the tape and two series of laterally spaced stitch loops on the other face of the tape, one series being engaged by a first knitting needle and the second series being engaged by a second knitting needle.
 3. A method according to claim 1 wherein the series of coupling elements is of coil fastener construction.
 4. A method according to claim 1 wherein the series of coupling elements is of meander fastener construction.
 5. A method according to claim 1 wherein a cord or braid is disposed between arms of the coupling elements and extends longitudinally of the series of elements.
 6. A method according to claim 1 wherein the series of coupling elements is guided through a tubular guide to its position adjacent an edge of the tape being knitted.
 7. A warp-knitting machine for making a sliding clasp fastener stringer, the machine having a knitting zone and comprising a row of knitting needles for knitting a carrier tape of the stringer, a plurality of guide bars each carrying yarn guides, a tubular guide having a lower end disposed to guide a series of interconnected coupling elements to a predetermined position in the knitting zone adjacent one end of the row of knitting needles, a sewing needle disposed at the front of the machine and means for reciprocating the sewing needle through a plane containing the row of knitting needles in a position beneath the tubular guide whereby during use the sewing needle passes a binding thread from the front to the rear of the machine, said thread passing around coupling elements being guided from the lower end of the tube, the needle coacting with at least one of the knitting needles to knit the binding thread into the tape and secure the elements thereto.
 8. A machine according to claim 7 wherein the tubular guide is supported in a fixed position relative to the plane of movement of the knitting needles.
 9. A machine according to claim 7 wherein means are provided for moving the sewing needle in directions in the lapping sense of the yarn guides when the needle is at the front of the machine so that the needle acts to form stitch loops of binding thread on at least two different knitting needles of the machine. 